LONDON -- The shares of London Stock Exchange (LSE:LSE) (NASDAQOTH:LDNXF) have rallied 6.6% to 1,423 pence today after the exchange operator reported a 7% expansion in full-year revenue to 726 million pounds.

However, LSE revealed that its adjusted pre-tax profit had declined 5% to 381 million pounds after incurring a 12% increase in operating costs. This escalation in expenses was mostly due to higher acquisition costs after the company purchased a majority stake in LCH.Clearnet earlier this year.

Commenting on the results, LSE chief executive Xavier Rolet said:

We have expanded our scale and reach, launched innovative new products and partnered with customers to develop new ventures. FTSE has performed well and is embedded as a core part of our business, and MillenniumIT has increased its third party sales as well as delivering key technology upgrades for the Group. These achievements, and other initiatives we have undertaken to become more efficient and diversify our business, have laid strong foundations on which to continue to build and drive the Group forward. We are optimistic about the year ahead and we will continue to focus on building best in class capabilities, extending our global footprint and to developing opportunities, now with LCH.Clearnet as part of the Group.

With a market cap of 3.8 billion pounds, LSE's shares are valued at 13 times today's reported earnings and offer a prospective dividend yield of 2.1%. Of course, whether that valuation, today's results, and the future prospects for the financial sector all combine to make shares of LSE a buy remains your decision.

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Mark Rogers has no position in any stocks mentioned. The Motley Fool has no position in any of the stocks mentioned. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.